Description

IPR005474 is a Transketolase, N-terminal.

<p>This entry represents the N-terminal domain of a group of transketolase proteins widespread among all cellular organisms.</p> <p>Transketolase [ec:2.2.1.1] (TK) catalyses the reversible transfer of a two-carbon ketol unit from xylulose 5-phosphate to an aldose receptor, such as ribose 5-phosphate, to form sedoheptulose 7-phosphate and glyceraldehyde 3- phosphate. This enzyme, together with transaldolase, provides a link between the glycolytic and pentose-phosphate pathways. TK requires thiamine pyrophosphate as a cofactor. In most sources where TK has been purified, it is a homodimer of approximately 70 Kd subunits. TK sequences from a variety of eukaryotic and prokaryotic sources [[cite:PUB00000209], [cite:PUB00000362]] show that the enzyme has been evolutionarily conserved. In the peroxisomes of methylotrophic yeast Pichia angusta (Yeast) (Hansenula polymorpha), there is a highly related enzyme, dihydroxy-acetone synthase (DHAS) [ec:2.2.1.3] (also known as formaldehyde transketolase), which exhibits a very unusual specificity by including formaldehyde amongst its substrates.</p> <p>1-deoxyxylulose-5-phosphate synthase (DXP synthase) [[cite:PUB00004906]] is an enzyme so far found in bacteria (gene dxs) and plants (gene CLA1) which catalyses the thiamine pyrophosphoate-dependent acyloin condensation reaction between carbon atoms 2 and 3 of pyruvate and glyceraldehyde 3-phosphate to yield 1-deoxy-D-xylulose-5-phosphate (dxp), a precursor in the biosynthetic pathway to isoprenoids, thiamine (vitamin B1), and pyridoxol (vitamin B6). DXP synthase is evolutionary related to TK. The N-terminal section, contains a histidine residue which appears to function in proton transfer during catalysis [[cite:PUB00001222]]. This entry represents the central section there are conserved acidic residues that are part of the active cleft and may participate in substrate-binding [[cite:PUB00001222]]. This group of proteins includes transketolase enzymes [ec:2.2.1.1] and 2-oxoisovalerate dehydrogenase beta subunit [swissprot:P37941] [ec:1.2.4.4]. Both these enzymes utilise thiamine pyrophosphate as a cofactor, suggesting there may be common aspects in their mechanism of catalysis.</p>

This description is obtained from EB-eye REST.

Associated GO terms

Unable to find any GO terms for the transcript with the identifier.

Associated Lotus transcripts 27

Co-occuring domains 1

A list of co-occurring predicted domains within the L. japonicus gene space: